- Tooth
- The structures within the mouth that allow for biting and chewing. Teeth have different shapes, depending on their purpose. The sharp canine and frontal teeth allow for biting, while the flattened, thick molars in the back of the mouth provide grinding surfaces for masticating food. All teeth have essentially the same structure: a hard crown above the gum line, which is attached to two or four roots by a portion called the neck. The roots are covered with a very thin layer of bone, and keep the tooth embedded in the bones of the jaw. The exposed exterior of the tooth is covered with tough enamel. Under the enamel is a thick layer of dentin, and in the center is the pulp. Blood vessels and nerves are found within the pulp.
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tooth 'tüth n, pl teeth 'tēth any of the hard bony appendages that are borne on the jaws and serve esp. for the prehension and mastication of food see MILK TOOTH, PERMANENT TOOTH* * *
n. (pl. teeth)one of the hard structures in the mouth used for cutting and chewing food. Each tooth is embedded in a socket in part of the jawbone (mandible or maxilla) known as the alveolar bone (or alveolus), to which it is attached by the periodontal membrane. The exposed part of the tooth (crown) is covered with enamel and the part within the bone (root) is coated with cementum; the bulk of the tooth consists of dentine enclosing the pulp. The group of embryological cells that gives rise to a tooth is known as the tooth germ.* * *
(t
th) pl. teeth [L. dens; Gr. odous] 1. any of the hard calcified structures set in the alveolar processes of the mandible and maxilla for mastication of food. In humans, there are two sets of teeth (dentes [TA]), deciduous and permanent. Each tooth consists of three parts: the crown (see corona dentis), the neck (see cervix dentis), and the root (see radix dentis). The solid part includes dentin, forming most of the tooth and resembling true bone; enamel, a very hard inorganic substance, covering the crown; and cementum, covering the root. In the center is the soft pulp (see pulpa dentis). See also dentition. 2. a structure resembling the tooth of an animal.
Schematic cross section of an anterior (left) and a posterior (right) tooth in the maxilla.
Medical dictionary. 2011.
